The numbers

Pentax introduced the MX as one of the smallest and lightest professional-level SLR cameras available in 1976, and continued production until the larger LX hit the market in 1985.

It uses K-mount bayonet lenses, and is reputed to have one of the biggest and brightest viewfinders of its day, as well as a complete line of available accessories including motor drive, data backs, interchangeable focusing screens, and even a 250-frame high-capacity magazine back.

The MX offers no auto-exposure, but boasts a fully-mechanical shutter with speeds form 1 second to 1/1000 second and Bulb. Multiple exposures are possible, too. The two SR44 batteries power the light meter only.

A mime playing the violin on the 16th Street Mall in Denver. (Daniel J. Schneider)

The film speed selector is on the shutter speed selector knob. Instead of a lift-and-turn arrangement, there’s a small silver button you press to release the outer ring and select the film speed.

The variable self-timer lever on the front rotates away from the lens mount, counting down from anywhere up to about 10 seconds at maximum rotation. Pushing the lever toward the lens actuates the depth-of-field preview. There is a hot shoe on top of the pentaprism housing.

The light meter uses an LED display in the viewfinder similar to the Pentax ME Super, with red, yellow and green LEDs indicating over- and under-exposure. The shutter speed is indicated by means of a clear disc that rotates to show the selected speed next to an arrow on the right-hand edge of the viewfinder. An optical display shows the aperture selected on the lens, too.

One of several seemingly random fountains placed in the center strip of Denver’s 16th Street Mall. (Daniel J. Schneider)

The rewind knob and take-up spool release button mirror those on the K1000, and the take-up spool itself works like that of the ME Super. There’s a shutter-ready indicator on the top cover next to the release, too.

The shutter release button has a rotating collar around it that locks the shutter when not in use, and the button is threaded for a standard cable release. Half-pressing the button activates the light meter.

The 40mm lens was the only pancake lens Pentax ever made for film cameras, and the lightest lens they ever made, period.

The MX is ever-so-slightly larger than the ME Super, but definitely smaller than the K1000 and Spotmatic. Visually, it looks almost identical to the ME Super, though, which is especially evident in the shape of the pentaprism housing.

Functionally, it’s definitely a middle point — a hybrid, almost — between the K1000 and the ME Super. The film advance looks and feels like that of the ME Super, the viewfinder is its equal and then some in terms of brightness and bigness, and the meter display design matches very closely. The mechanical shutter, film and shutter speed selectors, and the size and shape of the shutter release button all remind me of the K1000.

Late afternoon light plays across the face of a building in downtown Denver. (Daniel J. Schneider)

The outlier is the lock collar on the shutter release, which matches none of their other cameras up to that era. It does, however, remind me of the lock on the Pentax 6×7.

I did find the focus ring on the 40mm lens a little hard to locate by feel because it’s only about 2 millimeters wide, which led to accidental aperture changes. I got more used to it, though, and imagine you’d have no problem if you used this body-lens combo regularly.

The shutter speed selector is tight and takes a firm grip to turn, which meant operating it with my index finger as I do with most cameras was difficult or impossible. Based on the condition of the camera, I suspect that could be a result of its having hardly been used during its life.

The Pentax MX and 40mm f/2.8 might be the best SLR street photography kit I’ve tried. It’s diminutive and stealthy, but so obviously an SLR camera as not to draw as many stares as a TLR or many rangefinders. The shutter is exceptionally quiet for an SLR, with the mirror barely slapping at all. I’d guess it’s on par with my Leica IIIc in terms of overall volume.

The lens is great for “f/8 and be there” shooting; set the aperture to f/8 and the focus distance to 10 feet, and you’ll get sharp or acceptable focus on everything from about 6 feet to near-infinity. The big viewfinder makes composing quickly pretty easy, too.

Of course, the K-mount lens line includes tons of great lenses from both Pentax and third-party manufacturers, and with the range of accessories, this is a great choice for a lightweight walking-around camera with plenty of hidden potential.

This is the fifth Pentax camera I’ve reviewed, and it’s the fifth to earn all five stars. I’m sensing a trend. (I’ve also reviewed five Olympus cameras, but a couple of them have fared less well.)

Afraid I just don’t have anything bad to say about the Pentax MX, though. If you see one, snag it!

I know, right? I’ve decided to stick primarily with Nikon, but Pentax is a close second. If I find another one at some point I’ll keep you in mind!

Kevin MacNutt

I sadly sold mine in order to finance a lens purchase for one of my digital cameras, which I honestly shoot more often. I kind of regret doing that as the MX was a fantastic little camera. The reason I sold it was I shoot my Olympus OM 2 and OM 4 cameras more when I shoot film and I knew it was one of the few cameras I wasn’t using that much that was actually worth something.

Surprised you didn’t keep it. It’s the camera that truly started me down the Pentax rabbit hole, abandoning all other for a VERY long time, and I still now have more Pentax than anything else. It’s not even close.
But the MX…. oh the MX. It’s the only camera that I’ve had FOUR (or was it 5? yikes) of at one time. Only have two now – an early black model and a very late bright capped silver. They’ll never leave me. I use the black one by FAR more than any other 35mm camera I own. They’ve become a part of me. I enjoy shooting an LX, or a 67 or even some Konicas more overall (very slightly)… But if I had to keep just one camera, it’d be an MX.

Well, I just didn’t figure I needed more “keep” cameras … although I regretted selling it and have since received another as a gift from a friend that I intend to hang on to. I am more habituated to and have a much better selection of lenses for my Nikon 35mm SLRs, though, so they’ll still be my go-to for the foreseeable future, but I’m glad I have the MX in the wings. Too good not to hang on to!